Patient lift and transfer device

Abstract

A transfer device has a carriage supported on a base, movable between a home position and an extended position. A table assembly includes a lower table fixed to the carriage and an upper table coupled to the lower table, movable between a downward position in forcible contact with the lower table and an upward position having no contact with the lower table. The table assembly moves toward the extended position with the tables in forcible contact to place the table assembly underneath the object to be transferred while keeping the base stationary. The plates are separated to lift the object on the upper table while the lower table remains resting upon the support surface. The table assembly returns to the home position while supporting the object on the upper table and keeping the upper and lower tables separated. The device may operate in a bidirectional manner.

1. A method of transporting a patient from a bed to a hospital table, comprising:
 positioning a first side of a transfer device adjacent the bed, the transfer device having a base with wheels and support columns, slide frames attached to upper portions of the support columns, carriages slidably supported by the slide frames, and a table assembly carried by said carriages including separable upper and lower tables surrounded by respective upper and lower belts; 
 adjusting a height of the slide frames to a height of the bed; 
 moving the table assembly from a home position centered over the base to a first extended position at the first side of the transfer device with the upper and lower tables in forcible contact and the upper and lower belts counter-rotating to place the table assembly between the patient and the bed, while keeping the base stationary; 
 separating the upper and lower tables with the table assembly in the first extended position to lift the patient above the bed on the upper table while the lower table remains resting upon the bed; 
 moving the table assembly from the first extended position to the home position while supporting the patient on the upper table, keeping the upper and lower tables separated, with the lower table laterally supporting the transfer device and without any part of the base extending under the bed; 
 moving the transfer device on its wheels from the bed at a first location to the hospital table at a second location while supporting the patient on the upper table and keeping the upper and lower tables separated; 
 positioning a second side of the transfer device adjacent the hospital table; 
 moving the table assembly from the home position to a second extended position at the second side of the transfer device while supporting the patient on the upper table, keeping the upper and lower tables separated, with the lower table laterally supporting the transfer device and without any part of the base extending under the hospital table; 
 lowering the upper table into forcible contact with the lower table; and 
 moving the table assembly from the second extended position to the home position with the upper and lower tables in forcible contact and the upper and lower belts counter-rotating to offload the patient onto the hospital table, while keeping the base stationary; 
 wherein the upper and lower tables are separated and forced into contact by driving screw jack assemblies of vertical plate separators affixed to the carriages. 
 
   
   
     2. The method of  claim 1  wherein the table assembly moves to or from the home position at a speed that matches an eversion rate of the counter-rotating belts. 
   
   
     3. The method of  claim 1  wherein:
 the lower table and the upper table have a common lengthwise axis when the lower and upper tables are in forcible contact and when the lower and upper tables are separated; and 
 the lower and upper tables have left and right sides, and a leading edge of each side of the lower and upper tables is symmetric along the common lengthwise axis of the lower and upper tables. 
 
   
   
     4. A patient lift and transfer device comprising:
 a base having a plurality of wheels; 
 a first support column attached to said base at a first end thereof; 
 a second support column attached to said base at a second end thereof; 
 a first slide frame fixed to an adjustable upper portion of said first support column; 
 a second slide frame fixed to an adjustable upper portion of said second support column; 
 a first carriage slidably supported by said first slide frame, movable between a first extended position to a first side of said base, a home position centered over said base, and a second extended position to a second side of said base; 
 a second carriage slidably supported by said second slide frame, movable between a first extended position to the first side of said base, a home position centered over said base, and a second extended position to the second side of said base; 
 a lower table fixed at a first end to said first carriage and fixed at a second end to said second carriage, said lower table including a lower plate member surrounded by a lower belt; and 
 an upper table coupled to said lower table, said upper table including an upper plate member surrounded by an upper belt and being movable between a lowered position and a raised position when said carriages are in either of the first extended position and the second extended position, wherein said upper belt is in forcible contact with said lower belt when said upper table is in said lowered position, and said upper belt has slack when said upper table is in said raised position; 
 wherein said upper and lower tables are separated and forced into contact using vertical plate separators affixed to said first and second carriages having screw jack assemblies. 
 
   
   
     5. The patient lift and transfer device of  claim 4  wherein:
 said upper table and said lower table have a common lengthwise axis when said upper table is in either the downward position or the upward position; and 
 said lower and upper tables have left and right sides, and a leading edge of each side of said lower and upper tables is symmetric along the common lengthwise axis of said lower and upper tables. 
 
   
   
     6. The patient lift and transfer device of  claim 4  further comprising:
 a pad positioned on an upper surface of said upper plate member; and 
 a fabric-reinforced polytetrafluoroethylene sheet interposed between said pad and a top leg of said upper belt. 
 
   
   
     7. The patient lift and transfer device of  claim 4  wherein:
 outside surfaces of said upper and lower belts are coated with ethyl vinyl acetate; and 
 inside surfaces of said upper and lower belts are coated with polytetrafluoroethylene.